Answer: Event 1 is an example of a physical change and Event 2 is an example of a chemical change.
Explanation: Physical change is one in which there is no change in chemical composition of the substance. There is only a change in phase change.
Chemical change is a change in which there is a change in chemical composition and there might or might not be a phase change.
On Boiling, the water molecules remain bonded in the same form and only covert from liquid to gaseous form, thus is a physical change.
On Rusting of iron nail, the iron changes to iron oxide by combining with oxygen, there is a rearrangement of atoms and thus is a chemical change.
Metallic I’m pretty sure. :)
Answer:
D
Explanation:
When lead ions and sulfate ions bond, they form sediment so neither a nor b can be the answer.
The important thing is that two nitrate ions were originally bonded with one lead ion, while two potassium ions bonded with a sulfate ion.
Finally, since potassium and nitrate ions don't form sediment these two ions must remain. Therefore the answer is D
Answer:
2 CH2 + 3 O2 = 2 CO2 + 2 H2O
Explanation:
This is what I think that you meant by the question listed. When balancing a chemical equation, you want to make sure that there are equal amounts of each element on each side.
Originally, the equation's elements looked like this: 1 C on left & 1 C on right; 2 H on left & 2 H on right; 2 O on left and 3 O on right. Because these are not balanced, you need to add coefficients.
When adding coefficients, you need to make sure that all of the elements stay balanced, not just one that you are trying to fix. I know that some equations are really difficult to balance, and when that is the case, there are equation balancing websites that can help out.
However, what always helps me is making a chart and continuing to keep up with the changes I am making. It is a trial and error process.
Answer:
The answer to your question is: number 1
Explanation:
Third law of Newton: says that for every action ,there is an equal and opposite reaction.
So, if the child is pushing an object to the right, it will recipe the same amount of force that he is exerting to the object but in opposite direction.
Number 2 and 3 are incorrect because, because the third law of Newton says "an equal and opposite reaction", not slightly more or less.
Number 4 is wrong, it is not in agreement with Newton's third law of motion.
